As oligonucleotide-based modalities such as guide RNAs and siRNAs become more complex, it is increasingly difficult to separate products from impurities—which poses major challenges for purity, safety, and regulatory compliance. Purification methods such as strong anion exchange (AX) and ion-pair reversed-phase (IPRP) remain essential tools for purifying synthetic oligos, but separating closely related sequences, especially as their length and chemical complexity increase, calls for a novel approach.

In this GEN webinar, Joe Guiles, PhD, will describe an enhanced two-step oligonucleotide purification process using strong anion exchange with ion-pair reversed-phase (AX-IPRP) chromatography. This strategy is designed for high-resolution separation of impurities without requiring chemical tags or specialized equipment and is broadly applicable to diverse oligo sequences and ligand chemistries. Key takeaways include:

• The structural challenges of oligonucleotide length and chemical complexity for purification outcome and regulatory compliance.
• How the AX–IPRP workflow enables >80% purity for long guide RNAs (e.g., 100-mers) with high step recovery and minimal process complexity.
• Operational considerations for integrating these methods into existing manufacturing infrastructure, including resin selection, residual buffer control, and process control strategies.

A live Q&A followeded the presentation, offering a chance to pose questions to our expert panelist.

Produced with support from: